DOWN FLOW & DIRECT VENT (SEALED COMBUSTION) …by closing its manual shut off valve at test...

THERMO PRODUCTS, LLC. POST OFFICE BOX 237 DENTON, NC 27239 PHONE: 800- 476-4328

MG-521 ECN 5580-MA 190515

MADE IN USA

GAS-FIRED FURNACE DOWN FLOW & DIRECT VENT (SEALED COMBUSTION)

MODELS: GMD2-60N and GMD2-80N

INSTALLATION AND SERVICE MANUAL For installation in:

1. Manufactured Homes

2. Modular Homes/Buildings

3. Site Constructed—Residential (Single Story Dwellings)

:

FOR YOUR SAFETY Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this

or any other appliance.

WHAT TO DO IF YOU SMELL GAS Do not try to light any appliance.

Do not touch any electrical switch; do not use any phone in your building.

Immediately call your gas supplier from a neighbor’s phone.

Follow the gas supplier’s instructions.

If you cannot reach your gas supplier, call the fire department.

: If the information in these instructions is not followed exactly, a fire or explosion

may result causing property damage, personal injury, or loss of life.

: Improper installation, adjustment, alteration, service, or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information, consult a qualified installer, service agency, or fuel supplier.

: Do not use this appliance if any part has been underwater. Immediately call a qualified service technician to inspect the appliance and to replace any part of the electrical or control system that has been underwater.

PLEASE READ THESE INSTRUCTIONS PRIOR TO INSTALLATION, INITIAL FIRING, AND BEFORE

PERFORMING ANY SERVICE OR MAINTENANCE. THESE INSTRUCTIONS MUST BE LEFT WITH THE USER

AND SHOULD BE RETAINED FOR FUTURE REFERENCE BY QUALIFIED SERVICE PERSONNEL.

All installations and services must be performed by qualified service personnel.

1

I. SAFETY SECTION

This page and the following two pages contain various warnings and cautions

found throughout this furnace Service and Installation Manual. Please read and

comply with the statements on the cover and the statements below.

: This furnace is not to be used as a construction heater.

: When testing electrical equipment, always follow standard electrical

procedures and precautions.

: The area around the furnace should be kept free and clear of

combustible materials, especially papers and rags.

: This furnace uses an automatic hot surface ignition control. NEVER

try to ignite gas manually.

: If the temperature rise exceeds 85°F, the heat exchanger may fail

voiding the heat exchanger warranty resulting in property damage, personal

injury or loss of life.

: Burner adjustments must be confirmed by instrumentation. Failure to

use accurate or calibrated instrumentation to setup the burner may result in

reduced efficiency, sooting, and/or the production of hazardous carbon

monoxide gas.

: Any attempt to relocate safety controls or replace safety controls with

a control that is not approved or incompatible, may result in personal injury,

substantial property damage or death.

: If you do not follow these instructions exactly, a fire or explosion may

result causing personal injury, loss of life or property damage.

: HAZARD OF ASPHYXIATION: Negative pressure inside the closet with

closet door closed and the furnace blower operating shall be no more negative

than minus 0.05 inch water column.

: Do not obstruct any return air openings, including the return grille on

the furnace. To do so may cause the furnace to activate the high limit and shut

down or it may cause asphyxiation.

: Because of the potential of odorant fade, a gas leak may not be

detected by smell. If this furnace is installed below grade, contact your gas

supplier for a gas detector.


2

: All gas pipe connections must be leak tested using a strong soap and

water solution (with the gas turned on). Any leaks must be repaired immediately

after turning off the gas supply. A final test for gas leakage must be made after

purging the gas line.

: DO NOT wet electronic components during the leak test. Wetting

electronic components may damage circuitry and cause a hazardous situation.

Dry moisture from all leads and terminals if wetting occurs. Wait at least 24

hours for the circuit to fully dry before energizing the system.

: The furnace and its gas valve must be disconnected from the gas

supply during pressure testing of the gas supply system at pressures in excess

of 1/2 PSIG or 14.0 inches W.G. The furnace can be isolated from the gas supply

by closing its manual shut off valve at test pressures equal to or less than 1/2

PSIG or 14.0 inches W.G.

: Copper and brass tubing and fittings (except tin lined) shall not be

used if the gas contains more than a trace (0.3 grains per 100 cubic ft.) of

hydrogen sulfide gas. Check with your gas supplier.

: If you suspect there is a problem with the furnace, the venting system

or any other related problem, immediately contact a qualified service agency. If a

service agency is not available, contact your fuel supplier.

: Personal injury, or property damage, could result from major repair or

service of this furnace by anyone other than a qualified contractor. Only the

routine maintenance described in the user section of this manual should be

performed by the user.

: Do not block or obstruct air openings on the furnace or air openings

communicating with the area in which the furnace is installed.

: Do not allow the outside air intake to be blocked or obstructed by

vegetation, ice, snow or any other materials.

: Do not use this furnace if any part has been underwater. Immediately

call a qualified service agency to inspect the furnace and to replace any part of

the electrical or control system, which has been underwater.

: Should overheating occur or the gas supply fail to shut off, shut off

the manual gas supply valve to the furnace before shutting off the electrical

supply.


3

This page and the following page contain reproductions of the various warning

and instruction labels placed on the Thermo Pride Gas Furnace. Please read and

comply with the contents of these labels.


4


5

NAT. 60 000 #38 5,5 14,0 3,5 POUCES D'EAU W. C.

P.L. 60 000 #52 11,0 14,0 10,0 POUCES D'EAU W. C.

NAT. 80 000 2,45mm 5,5 14,0 3,5 POUCES D'EAU W. C.

P.L. 80 000 #53 11,0 14,0 10,0 POUCES D'EAU W. C.


6

TABLE OF CONTENTS

SECTION BEGINNING PAGE

I. SAFETY SECTION 1

II. GENERAL INSTRUCTIONS AND CLEARANCES 7

III. FURNACE SPECIFICATIONS 9

IV. INSTALLATION 11

A. ROOF JACK 11

B. STANDARD CHIMNEY 11

C. FURNACE LOCATION 11

D. BASE INSTALLATION 13

1. Combustible Floor Base Model: 70-BASE 13

2. Cottage Base Model: 01COT-BASE 14

E. ALCOVE INSTALLATION 15

F. CLOSET INSTALLATION 16

G. COMBUSTION AIR 17

H. GAS PIPING 19

I. ELECTRICAL WIRING 20

J. INITIAL START UP 22

K. ADJUSTMENT OF BTU INPUT RATE 22

L. BURNER ADJUSTMENT 24

M. SETTING TEMPERATURE RISE 25

N. FURNACE CHECKOUT PROCEDURE 26

V. INSTALLER’S INSTRUCTIONS TO USER 27

VI. STARTING THE UNIT 28

A. SEQUENCE OF OPERATIONS 28

VII. TROUBLESHOOTING 30

VIII. DEALER MAINTENANCE 36

A. ELECTRICAL 36

B. BURNERS 36

C. INDUCER BLOWER ASSEMBLY 37

D. INSPECTING THE VENTING SYSTEM 37

E. GASKETS/SEALING MATERIALS 38

F. HEAT EXCHANGER 38

G. HOUSE AIR BLOWER 38

H. EXTENDED SHUTDOWN 38

IX. USERS INFORMATION SECTION 39

A. WARNINGS & CAUTIONS 39

B. COMPONENT LOCATIONS 40

C. INSPECTION AREAS 40

D. FILTER LOCATION AND CLEANING 41


7

APPENDIX A – REPLACEMENT PARTS 42

APPENDIX B – WIRING DIAGRAM 44

II. GENERAL INSTRUCTIONS AND CLEARANCES

NOTE: READ THIS SECTION BEFORE STARTING INSTALLATION

1. This furnace is equipped with orifices for operation with natural gas. For

conversion to propane gas, see instructions in Gas Conversion Section of this

manual.

2. Any reference to L.P. or Propane gas in this manual, any other labels, or

markings on this furnace is to be construed to be propane HD-5. A commercial

grade of liquefied petroleum gases composed of a minimum of 90 percent liquid

propane (C8H8).

3. The selection of a furnace heating capacity for a proposed installation should be

based on a heat loss calculation made according to the manuals provided by the

Air Conditioning Contractors of America (ACCA) or the American Society of

Heating, Refrigeration and Air Conditioning Engineers, Inc. (ASHRAE).

4. It is recommended that a commercial available CO alarm be installed in

conjunction with any fossil fuel burning appliance. The CO alarm shall be

installed according to the alarm manufacturer’s installation instructions and be

listed in accordance with the latest edition of the UL Standard for Single and

Multiple Station Carbon Monoxide Alarms, UL 2034, or the CSA International

Standard, Residential Carbon Monoxide Alarming Devises, CSA 6.19.

5. The installer shall be familiar with and comply with all codes and regulations

applicable to the installation of these heating appliances and related equipment.

In lieu of local codes, the installation shall be in accordance with the current

provisions of one or more of the following standards.

a. Federal Manufactured Home Constructions & Safety Standard (HUD Total 24,

Part 280).

b. American National Standard (ANSI-119.2/NFPA-501C), for installations of all

recreational vehicles.

c. American National Standard (ANSI-Z223.1/NFPA-54), for installation of all gas-

fired furnaces.

d. American National Standard Electric Code (ANSI-C1/NFPA-70), for installation

of all electrical field wiring.


8

The gas-fired furnace has been investigated under the ANSI Z 21.47-CAN/CGA 22.3-

2001 CENTRAL FURNACE test standard. This gas fired unit is listed by Intertek

Testing Services and described as, “For installation as central furnace special type for

single story dwelling.”


9

: The area around the furnace must be kept free and clear of


: This furnace is not to be used as a construction heater.

6. Definitions of "combustible" and "non-combustible" materials as presented in the

1999 version of the National Fuel Gas Code, ANSI Z223.1-1999/NFPA 70-1999, are

as follows:

a. Combustible material:

“...materials made of or surfaced with wood, compressed

paper, plant fibers, or other materials that are capable of

being ignited and burned. Such material shall be

considered combustible even though flame proofed, fire-

retardant treated, or plastered.”

b. Non-combustible material:

“...material that is not capable of being ignited and

burned; such as material consisting entirely of, or a

combination of, steel, iron, brick, tiles, concrete,

slate, asbestos, glass, and plaster.”

This heating appliance must be installed with clearances to combustible material

surfaces of not less than the minimum distances given below. Also, allow ample

clearances for servicing the furnace for easy access to the air filter, blower assembly,

burner assembly, controls, and vent connections.

MODELS GMD2-60N and GMD2-80N CLOSET ALCOVE

FRONT

BACK

SIDES

ROOF JACK

VENT CONNECTOR

TOP

PLENUM SIDES

TOP AND SIDES OF DUCT

BOTTOM OF DUCT

6”

0”

0”

0”

6”

1”

1”

1”

1”

18”

0”

0”

0”

6”

1”

1”

1”

1”


10

III. FURNACE SPECIFICATIONS

MODEL GMD2-60 GMD2-80

HEAT INPUT RATE (BTUH) 60,000 80,000

HEATING CAPACITY (BTUH) 49,000 65,000

BURNER ORIFICE-NAT. GAS (MM) #38 2.45

BURNER ORIFICE-PROP. GAS (DMS) #52 #53

GAS SUPPLY PRESSURE (IN.W.G.)

MINIMUM REQUIRED

PROPANE 11 11

NATURAL 5.5 5.5

MAXIMUM ALLOWED

PROPANE 14.0 14.0

NATURAL 14.0 14.0

GAS MANIFOLD PRESSURE (IN. W.G.)

PROPANE 10 + 0.3 10 + 0.3

NATURAL 3.5 + 0.3 3.5 + 0.3

VENT PIPE SIZE (INCHES) 4 4

DESIGN TEMPERATURE RISE (°F) 70 70

SEASONAL EFFICIENCY

(AFUE*, %) 82 81

*AFUE - INCLUDES STEADY STATE THERMAL EFFICIENCY AND OFF CYCLE

LOSSES.

ELECTRICAL RATINGS AND SETTINGS:

ELECTRICAL SUPPLY: 115 VAC / 60HZ / 1 PHASE

MAXIMUM TIME DELAY TYPE FUSE OR HACR BREAKER RATING: 15 AMPS

TOTAL RATED CURRENT (AMPS): 7.15 (GMD2)

NOMINAL HEAT ANTICIPATOR SETTING -- 0.8 mA (GMD2)

DIMENSIONS & WEIGHTS:

CABINET: WIDTH - 18 IN., DEPTH – 25-3/4 IN., HEIGHT - 57 IN.

NO.70 MOBILE HOME BASE: WIDTH - 18-5/16 IN., DEPTH - 24¼ IN., HEIGHT - 4 IN.

WARM AIR DUCT: WIDTH – 12 IN., DEPTH – 12 IN.

COTTAGE BASE: WIDTH – 18-3/16 IN., DEPTH - 24¼ IN., HEIGHT – 14 IN.

FILTER QUANTITY & SIZE: 1 – 18” x 24 “

APPROXIMATE SHIPPING WEIGHT: 165 LBS.

PRODUCT LISTED UNDER ETL FILE NUMBER –


11

BLOWER DATA

GMD2-60

MANUFACTURER: MORRISON PRODUCTS, INC.

BLOWER MODEL: 10-7, DIRECT DRIVE

NOMINAL MOTOR POWER OUTPUT (HORSEPOWER): 1/3

TYPICAL AIRFLOW @ SPECIFIED EXTERNAL

STATIC PRESSURES (SCFM @. IN.W.G.):

ESP (IN W.C.) 0.2 0.5

LOW SPEED: 759 694

MEDIUM LOW

SPEED: 907 809

MEDIUM HIGH

SPEED: 1096 934

HIGH SPEED: 1207 1029

GMD2-80

MANUFACTURER: MORRISON PRODUCTS, INC.

BLOWER MODEL: 10-9, DIRECT DRIVE

NOMINAL MOTOR POWER OUTPUT (HORSEPOWER): 1/3

TYPICAL AIRFLOW @ SPECIFIED EXTERNAL

STATIC PRESSURES (SCFM @. IN.W.G.):

ESP (IN W.C.) 0.2 0.5

LOW SPEED: 712 640

MEDIUM LOW

SPEED: 870 760

MEDIUM HIGH

SPEED: 1100 886

HIGH SPEED: 1258 1003

ALL SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE.


12

IV. INSTALLATION

A. ROOF JACK

The roof jack assembly and accessories must be listed by a nationally recognized

testing agency for the appropriate heating fuel.

The roof jack assembly must be installed according to the vent manufacturer’s

instructions prior to the furnace installation. (Refer to Figure 2 for flue location on

furnace.) Adapters for pitched roofs as well as extended barrel length roof jacks are

available from other suppliers.

All vent seams and connections must be sealed with high temperature silicone caulk.

B. STANDARD CHIMNEY

When installed as a central furnace special type for single story dwelling, venting into a

metal vent system approved by a nationally recognized testing agency for the

appropriate heating fuel type is permitted. Lined masonry chimneys are acceptable

when sized appropriately. The minimum chimney size should equivalent to the inside

free area of the 4-inch diameter vent collar exiting the furnace, or 12.5 square inches.

Maximum chimney sizes and acceptable installation practices are referenced in the

following publication. When installing the GMD2-80N, refer to Appendix G of the latest

edition of the installation standard NFPA 54, National Fuel Gas Code.

C. FURNACE LOCATION

1. For best performance, locate the furnace so that it is centralized with respect to the

duct system.

2. This furnace is only intended for installation with free air return through the furnace

door louvers. c CAUTION: DO NOT connect a ducted return air system directly to

the furnace. Improper installation may create a fire hazard and damage internal

equipment, as well as void all manufacturers’ warranties.

3. This furnace may be installed on combustible flooring when utilizing either the No. 70

counterflow floor base, for below the floor duct systems, or with the cottage base, for

floor level air distribution. See Figures 1A and 1B for depictions of the No. 70 and

the cottage bases.

4. This furnace is listed for closet, alcove, or freestanding applications. All applications

must comply with the requirements of this manual.


13

Combustible Floor Base

Model: 70-BASE

Figure 1A

Cottage Base

Model: 01COT-BASE

Figure 1B

Coil Cabinet

Model: CE111S

Figure 1C

CE111S


14

D. BASE INSTALLATION

1. Combustible Floor Base Model: 70-BASE

Use the base bottom panel as a template to mark floor opening locations (see

Figure 2). Cut a square opening in the floor for the supply air connector duct. Cut the

opening 1-inch larger than the square template opening. (duct requires 1-inch

clearance to combustible floor). Cut a combustion air duct opening in the floor 1/8-

inch larger than the template opening.

Figure 2

After cutting openings in the floor, place the bottom panel in position. Mark the

square opening location on the distribution duct at the connection point of the

connector duct. Remove the bottom panel. Cut an opening in the distribution duct

slightly larger than the connector duct. (refer to Figure 2 for location of this cut.) Cut

the connector duct to length. Install the connector duct. Bend over each tab. Insure

an airtight seal by using high temperature sealant or tape on the joint. Reinstall the

bottom panel over the connector duct. Insert and secure the combustion air duct. Put

the base top assembly in place (see Figure-3).

c CAUTION: A combustion air duct must be used. If the underside of the

mobile home is skirted or enclosed (e.g. enclosed in a crawlspace), the

combustion air intake should exit through the skirting, or enclosure, if at all

possible. All joints and seams of supply ducts and combustion air ducts must

be closed with a sealing method suitable to the application conditions and

temperatures (e.g. high temperature silicone caulk and/or aluminum tape).


15

If the combustion air passageway cannot terminate outside of the skirting or

enclosure, a permanent opening with a minimum of 50 square inches of

unobstructed infiltration (free area) for ventilation air must be provided for

adequate combustion. This permanent opening must be located no less than 12

inches from the bottom of the enclosure or skirting.

Figure 3

Slit the corners of connector duct down to the top of the base assembly. If metal

projects more than 1-inch above the top of the base assembly, trim the flanges down

to 1-inch. While the top of distribution duct is being pulled up with one hand, bend

down each side of the connector duct tightly to the base assembly with the other

hand. This assures a tight connection between the base assembly and the connector

duct and that the distribution duct will be full size. Use high temperature tape and/or

high temperature silicone caulking on all joints and seams to minimize air leakage.

Secure the base assembly to the floor with two screws in the front flange.

2. Cottage Base Model: O1COT-BASE

The O1COT-BASE cottage base (Figure 1B) is required for a freestanding cottage

base installation. The cottage base is designed to permit the installation of a 6-inch

x 14-inch register in each of the two side panels and the front panel.


16

c CAUTION: A permanent opening with a minimum of 50 square inches of

unobstructed infiltration (free area) for ventilation and combustion air must be

provided to the interior of the structure. Additional make-up air may need to be

supplied to the interior of the structure to compensate for exhaust fans,

appliances, or vents, which consume air from the interior of the structure.

Refer to the assembly installation instructions included with OM1COT-BASE cottage

base for additional information.

3. Coil Cabinet: CE111S

The CE111S coil cabinet (figure 1C) is for applications requiring air conditioning.

The coil cabinet is designed to have the combustion air brought in from the bottom

thru a flexible hose, supplied with the cabinet. Refer to section G Combustion air of

this manual for further instructions on the combustion air termination and

connections. For additional information refer instructions provided with the coil

cabinet.

E. ALCOVE INSTALLATION

In this application, a minimum of 18

inches of clearance must be provided

to the front of the unit. Refer to

Figure 4.

Alcove installations must use the No.

70 mobile home base.

Note – access to diagnostic view port.

Refer to section G. COMBUSTION AIR

for additional combustion air

requirements.


17

Figure 4

F. CLOSET INSTALLATION

c WARNING: HAZARD OF

ASPHYXIATION: A suction

effect will occur when the

furnace is operating inside the

closet with the closet door

closed. For proper operation,

the furnace blower shall create

no more than a 0.05-inch water

column pressure differential

between the closet and the

adjoining space.

Figure 5

1. The return air opening into the closet is to have a minimum free area of 250 square

inches, (refer to Figure 5).

2. The return air opening may be located in the top, the center or (ideally) the bottom

of the closet door, or sidewall.


18

: Do not obstruct any return air openings, including the return grille on

the furnace. To do so may cause the furnace to activate the high temperature

limit and shutdown, or it may cause asphyxiation.

3. The cross-sectional area of the return air grille leading into the closet (when located

in the floor or ceiling) shall not be less than 250 square inches.

4. The total free area of openings in the floor or ceiling registers serving the return air

system must be at least 350 square inches. At least one register must be located

where it is not likely to be covered by carpeting, boxes, furniture, or any other

objects.

5. Materials located in the return air system must have a flame spread classification of

200 or less.

6. Wiring materials located in the return air duct system must conform to Article 300-22

of the latest edition of the National Electrical Code, NFPA 70.

7. Gas piping shall not be located in, or extend through, the return air duct system.

8. Refer to section G. COMBUSTION AIR for additional combustion air requirements.

G. COMBUSTION AIR

c CAUTION: Flexible, spiral, or corrugated duct is not recommended, due to the

relatively high-pressure drop associated with air movement through this type of

passageway.

The furnace requires the proper amount of combustion airflow through the combustion

air intake to combust the fuel cleanly and efficiently. An inadequate combustion air

supply can result in unsafe and erratic operation of the burner, sooting of the

combustion chamber and the heat exchanger, and possibly, offensive fuel odors. Refer

to chapter 5.3 of the National Fuel Gas Code, ANSI Z223.1 / NFPA 54-1999, or latest

edition for application specific combustion air requirements.

The preferred location of the outside combustion air intake terminal (e.g. an optional

stainless steel intake hood, part no. AOPS7402) is through the side of the structure,

skirting, or enclosure. An acceptable alternate location is under the structure in the

skirted or crawlspace area providing a minimum of 50 square inches of free area exists

around the perimeter for outside combustion air to be drawn through. The opening of

the termination must be at least 7 inches below the top of the floor.

The 70-base/coil cabinet is shipped with a combustion air duct that must be installed in

the bottom of the base enclosure, before the furnace is installed. This 2-inch by 7-inch


19

duct is shipped in two pieces. High temperature silicone sealant should be applied to

both vertical seams, before it is snapped together with all four flanges on the same end.

High temperature silicone must be applied to the flanges. The combustion air duct can

then be inserted through the opening in the floor base model no.70. When the

combustion air duct has been inserted completely, secure the duct to the combustion

adapter with self-tapping sheet metal screws, refer to Figure 6. Make certain that the

flanges, duct, and adapter are completely sealed to the burner enclosure base with

high temperature silicone caulk. A 3-inch round to 7-inch x 2-1/4 inch rectangular

adapter plate is supplied with the furnace for adapting the 3-inch round flex combustion

air duct to the 2-inch x 7-inch combustion air duct.

Recommended materials for the combustion air duct are smooth, round, galvanized

steel duct or schedule 20 PVC pipe. The maximum intake duct length allowed is

equivalent to 40-feet of straight duct. Reduce this length by 6-feet for the intake hood

and each 90-degree elbow used, and by 3-feet for each 45-degree elbow used the

combustion air duct.

Optional combustion air - a 4” round duct may be used by connecting a 3 x 4 reducer

to the 3” flex duct supplied with the furnace.


20

Figure 6


21

H. GAS PIPING

: Because of the potential of the odorant to fade, a gas leak may not be

detected by smell. If this furnace is installed below grade, contact your gas

supplier for a gas detector.

: With the gas piping pressurized, all gas piping connections must be

leak tested using a strong soap and water solution. Any leaks must be repaired

immediately after turning off the gas supply. A final test for gas leakage must be

made after purging the gas line.

: DO NOT wet electronic components during the leak test. Wetting

electronic components may damage circuitry and cause a hazardous situation.

Dry moisture from all leads and terminals if wetting occurs. Wait at least 24

hours for the circuit to fully dry before energizing the system.

: The furnace and its gas valve must be disconnected from the gas

supply during pressure testing of the gas supply system at pressures in excess

of 1/2 PSIG (13.9 inches W.G.). The furnace can be isolated from the gas supply

by closing the manual gas shutoff valve serving the appliance at test pressures

equal to, or less than, 1/2 PSIG or (13.9 inches W.G.).

: Copper and brass tubing and fittings (except tin lined) shall not be

used if the gas contains more than a trace (0.3 grains per 100 cubic ft.) of

hydrogen sulfide gas. Check with your gas supplier.

Sizing and installation of fuel lines must be in accordance with federal, state, and local

regulations.

A qualified installer or service person must install all gas piping and perform all

required testing.

Piping from the natural gas meter to the furnace shall be in accordance with

requirements of the local gas utility. Piping from the propane tank to the furnace must

follow the recommendations of the gas supplier. In the absence of local codes

governing gas piping selection and installation, follow the National Fuel Gas Code,

ANSI Z223.1 / NFPA 54-1999, or latest edition.

A readily accessible, manual gas shutoff valve (design-certified for the applicable gas)

with a non-displaceable rotor member shall be installed within six (6) feet of the

furnace.

A pipe union, or flanged connection, shall be provided directly up stream of the burner

to allow burner removal. Unions must be of a ground joint type or flange-jointed type

using a gasket resistant to the corrosive effects of LP gases. Pipe dope or sealant


22

design-certified to be resistant to the action of the LP gases should be used on all

threaded joints.

The burner is setup to be piped to the gas supply through the left-hand side of the

furnace. For service purposes, it is recommended the gas union be located inside the

furnace.

A drip leg must be used on both propane and natural gas installations immediately

upstream of the furnace in order to trap oil, condensate, and other impurities which

might otherwise lodge in the gas valve, or plug the main burner orifice. A drip leg shall

be provided at the outlet of the gas meter when there is excessive condensation

between the gas meter and the furnace.

Failure to install drip leg(s) may void the manufacturer’s limited warranty on the

furnace.

For natural gas, the maximum supply pressure is 14.0 in. W.G. and the minimum

supply pressure, for purposes of input adjustment, is 5.5 in. W.G.

For propane gas, the maximum supply pressure is 14.0 in. W.G. and the minimum

supply pressure, for purposes of input adjustment, is 11.0 in. W.G.

I. ELECTRICAL WIRING

: When testing electrical equipment, always follow standard electrical


All electrical wiring must be installed in strict accordance with local ordinances and

codes. In the absence of local ordinances and codes, all electrical wiring must conform

to the requirements of the National Electric Code, ANSI/NFPA 70-1999, or latest

edition.

1. Electrical Branch Supply Circuit

Route all electrical wiring to the left side of the furnace. The power supply circuit to

the furnace must be installed and grounded in accordance with the provisions of the

National Electrical Code, ANSI/NFPA-70-1999, or latest edition, and all local codes

having jurisdiction.

2. Connection Of Power Supply Wires

a. Remove the cover from junction box. b. Insert 115 VAC wires through the strain relief bushing (or conduit connection as

applicable) on the left side of the furnace junction box.


23

c. Connect the “hot” wire to the black wire.

d. Connect the “neutral” wire to the white wire.

e. Connect the “ground” wire to the green wire.

f. Reinstall and secure the junction box cover with the original mounting screws.

3. Connection Of Room Thermostat Wires

NOTE: Class 1 thermostat wire must be used inside the furnace burner

compartment.

a. Insert 24 VAC wires through the plastic grommet on the left side of the furnace

casing.

b. Connect the thermostat wires to the integrated furnace control (refer to the wiring

diagram).

c. Connect the thermostat wires to the room thermostat.

IMPORTANT: The room thermostat should be installed 4 to 5 feet above the floor

on an interior wall which is relatively free from direct sources of heat (sunlight or

supply airflow) or exposure to cold (drafts from open windows and doors). The

nominal anticipator setting is 0.8 amperes, for the GMD (refer to the thermostat

literature for additional information).

Five-conductor thermostat wire is recommended for 24 VAC, low-voltage, control

circuit wiring. How ever only 2 wires are required for the furnace (a heating

application only).

Electrical Wire Diameter Maximum Recommended

Thermostat Wire Length

(AWG)

(Feet)

24 55

22 90

20 140

18 225

Once the furnace is installed, check the thermostat anticipator for proper nominal

setting.

1. Connect a multimeter, capable of reading milliamps (mA), in series

with the low voltage wires to the thermostat.

1. Increase the thermostat setting, or create a “call for heat”.

2. Read the value of the thermostat current, in milliamps.

3. Adjust the heat anticipator of the thermostat to the value read by the

multimeter.


24

If the heat anticipator is set too high, the furnace may delay activation of a heating

cycle for too long. If the heat anticipator is set too low, the furnace may cycle too

frequently. Either condition may not provide optimal comfort to the homeowner.


25

J. INITIAL START UP:

This furnace does not have a pilot. It is equipped with a hot surface igniter, which

automatically lights the burner. Do not attempt to light the burner by hand. Check the

following items before the initial start-up.

1. Check all wiring for proper hook up. Tighten any loose connections.

2. Using a soap solution, leak test gas piping connections.

3. Check all tubing connections to the pressure switch, inducer, burner box, and gas

valve and make sure they are connected firmly at all their connection points.

4. Check flue pipe, combustion air inlet, and all joints for tightness and to make sure

there is no blockage.

5. Make sure air filter is in place.

6. Make sure the outside vent and air intakes are installed according to instructions

and are free from blockage.

OPERATING INSTRUCTIONS:

: Turn off power to furnace before it is placed into service. The gas

piping system must have been leak tested by a qualified heating contractor.

(See Section IV, H, of these instructions on the installation of gas piping).

: It may be necessary to purge the air out of the gas line for initial start-

up of the furnace after installation. A qualified heating contractor should do this.

If excessive gas escapes when purging the gas supply at the union, allow the

area to ventilate for at least 15 minutes before attempting to start the furnace.

Propane gas is especially dangerous because the specific gravity of propane gas

allows it to accumulate at floor level at a dangerous concentration.

: Heat exchanger oil will burn off on initial firing creating an unpleasant

odor. To prevent this odor from occurring more than once, it is suggested that:

1. A window(s) be opened.

2. The thermostat be set at highest setting.

3. The furnace remains running at conditions 1&2 for 30 minutes or until odor

has dissipated.

K. ADJUSTMENT OF HEAT INPUT RATE:

The orifices for this furnace were sized: 1) for natural gas having a heating value of

1025 BTU per cubic foot and a specific gravity of .65, or 2) for liquefied propane gas

with a heating value of 2500 BTU per cubic foot and a specific gravity of 1.55. The

rating label inside the furnace vestibule will specify which gas your furnace is orificed

for. If the furnace is installed at an altitude that is more than 2,000 feet above sea

level, it is mandatory the input to the burner be reduced 4.0% for every 1,000 feet that it

is above sea level. If the furnace is installed at an elevation of 5,000 feet, its input


26

must be reduced 20.0%. Example: a furnace rated at 80,000

BTU at sea level must be reduced to a firing rate of 64,000 (80,000 x .80 = 64,000) at

an elevation of 5,000 feet. If the furnace is installed at an elevation of 2,000 feet or

less, no reduction in input is required. Your gas supplier may supply you with the

correct orifice sizing information.

To check the heat input rate of your natural gas furnace, allow the unit to operate for 10

to 15 minutes and proceed as follows:

a. Call your gas supplier and ask for the BTU content (heating value) of one cubic foot

of the gas, supplied to the installation area. An alternate approach is to assume a

value of 1025 BTU/Cu Ft, which is the national average.

b. With all other gas appliances turned off and using a stopwatch, clock the time

required for the (small) dial on the gas meter to make one full revolution. The meter

dial will state the cubic feet of flow for one revolution usually one, two or five.

FORMULA: BTU/Cu Ft x Number of Cu Ft x 3600 Seconds = Input BTU/hr

Seconds for one revolution

EXAMPLE: 1025 BTU/Cu Ft x 2 Cu Ft x 3600 = 78,678 BTU Input

93.80 Seconds

Check the model number of the furnace, the input rate, the type of gas, and the

manifold pressure on the rating label located in the burner vestibule. If using the above

example, the furnace is a GMD2-80N model and the input rate is 78,678 BTU/hr. The

input rate would be acceptable because it was within + 2% of the listed input of 80,000.

c. Make sure that the gas supply pressure to the furnace is within the allowable range

of 5.5" to 14" WC pressure on natural gas and 11.0" to 14.0" WC on propane gas. The

pressure to the furnace must be checked while the furnace burner and any other gas

appliances on the same supply system are operating, using the 1/8 in. NPT manifold

pressure tap shown in figure 8.

GAS PRESSURE CHART FOR ALL GMD2-60 and GMD2-80 MODEL

FURNACES

SUPPLY PRESSURE MANIFOLD PRESSURE

NAT MAX 14” WC

MIN 5.5” WC 3.5 + .3” WC

PROPANE MAX 14” WC

MIN 11” WC 10.0” + .3” WC


27

TABLE 2

This gas furnace is equipped with a fixed orifice sized for the manifold pressure shown

on the rating label. The input can only be increased, or decreased, by adjusting the

manifold pressure. Remove the 1/8" threaded pipe plug located on the gas manifold.

Use a U tube manometer or recently calibrated pressure gage to measure the pressure.

To adjust the pressure, remove the screw cap from the regulator on the gas valve and

using the adjustment screw. Decrease the pressure by turning the screw

counterclockwise or increase it by turning the screw clockwise.

c CAUTION: ADJUSTMENTS TO THE LISTED PRESSURE MUST NOT EXCEED

0.3" WC A 0.3" WC adjustment will increase or decrease the input approximately 4.0%.

Replace screw (cap) when adjustment is complete.

The correct input can be assumed if the furnace manifold pressure is the same as that

shown on the rating label if a gas meter is not available for natural gas or the unit is

installed on an unmetered propane gas supply.

Shut off the gas supply to the furnace. Remove the pressure gage and re-install the

pipe plug using a thread compound resistant to the action of LP gases.

If the rated input cannot be obtained with the present orifice at the correct pressure,

your local gas supplier may assist in sizing the proper orifice. Thermo Products

Engineering Department will gladly assist in sizing the orifice if you provide them with

the heating value in BTU per cubic foot and the specific gravity of the fuel gas.

L. BURNER ADJUSTMENT

: The GMD2-60 and GMD2-80 furnace models utilize an in-shot burner

design that does not require an air shutter adjustment (air shutters are not used)

for proper flame characteristics. Burner box access cover must always be

secured with all screws in place and tightened before operating furnace.

This unit is designed to not require any burner adjustment. The flames should be

checked by looking through the sight glass located on the burner box. Burner flames

should be clear, blue, and almost transparent in color. (See Figure 8). NOTE: It is not

unusual to have mostly blue flames with yellow or orange tips visible in the tube for

propane gas.


28

Figure 8

M. SETTING TEMPERATURE RISE

The GMD2-60N and GMD2-80N is designed and wired at the factory for a heating

blower speed that should result in an approximate temperature rise of 70F.

The blower motor is wired on low speed for heating mode of the GMD2-60N.

The blower motor is wired on medium low speed for heating mode of the GMD2-80N.

The temperature rise through the furnace may vary depending on the duct system,

elevation, heating value, etc. for each installation.

After 10 to 15 minutes of continuous operation, the temperature rise through the

furnace must fall within a range of 55F to 85F. If the outlet or supply duct

temperature is too high, check to make sure the return air filter is clean, the return air

registers are free from obstruction, the outlet registers are properly adjusted and clear,

and the supply and return air ducts are open.

The circulating air blower is not moving enough air if the supply air temperature is still

too high. Before proceeding further, turn off the power supply to the furnace and

remove the blower door. The speed of the blower must be increased by changing the

speed tap from the motor (see wiring diagram). This is accomplished by locating the

control panel attached to the blower housing and switching the blower lead, which

should be connected to the “Heat” terminal on the integrated furnace control, with one

of the higher speed blower leads attached to a terminal marked “Park”. Be sure to

attach any unused blower leads to a terminal marked “Park”. Replace the blower door

and turn on the power supply.


29

N. FURNACE CHECKOUT PROCEDURE

Before any system of gas piping is finally put into service, it shall be carefully tested to

assure that it is gas tight as indicated in section IV. H. Gas Piping of this manual.

NOTICE: All controls on the unit should be checked for proper functioning prior to the

qualified service personnel leaving the job site. Specifically the following should be

checked:

With furnace in normal heating operation, check to make certain blower will start and

stop automatically under control of integrated fan control.

1. Check safety limit control as follows:

a. Shut off incoming power.

b. Block return air opening or disconnect blower motor leads.

c. Restore power to furnace.

d. Set thermostat above room temperature calling for heat.

e. When high air temperatures are reached in furnace at limit control setting with

blower out of operation, burner should shut off.

f. Shut off electrical power.

IMPORTANT: Remove blockage or reconnect blower motor and restore power.

2. Make certain thermostat will automatically start and stop furnace.

3. Block the flue pipe outlet gradually until the pressure switch functions shutting off

the main burners.

4. Block the inlet gradually until pressure switch functions shutting off the main

burners.

IMPORTANT: Remove flue or air inlet blockages when done.


30

V. INSTALLER'S INSTRUCTIONS TO USER:

After completing the installation, the installer shall inform and/or demonstrate to the

homeowner:

1. The location of all the instructions in the furnace must be kept along with

instructions for any accessories in the plastic pouch near the furnace.

2. The location and use of the manual gas shut off valve and furnace electrical

disconnect switch. Instruct user to always shut off gas before shutting off electric

power.

3. The sequence of operation of the furnace.

4. The correct operation and maintenance of the appliance as outlined in the Users

Information section of this manual.

5. That failure to maintain and operate this furnace in accordance with these

instructions could result in hazardous conditions, bodily injury, and property

damage and may void the limited warranty on the furnace.

6. Review with and encourage the user to read the label reproductions and all

warnings and instructions outlined on the front cover and in sections I, II and III of

this manual and in the Users Information section of this manual.

7. Recommend the user has a qualified heating contractor inspect the furnace at the

start of each heating season. Inform the user of the frequency of inspection

required for reach item in the User Information Section of this manual.

8. Should the furnace not operate after installation – note diagnostic code through

view port prior to removing door.


31


32

FLAME MUST BE DETECTED WITHIN

4 SECONDS IF FLAME IS DETECTED, THE DELAY-TO-FAN-ON

TIME BEGINS (45 SECONDS)

IF FLAME IS NOT DETECTED, THE GAS VALVE

IS DE-ENERGIZED, THE IGNITOR IS TURNED OFF AND

THE CONTROL BOARD CONTROL GOES INTO "RETRY" SEQUENCE

POWER INTERRUPTION SYSTEM SHUTS OFF,

RESTARTS WHEN POWER IS RESTORED.

PRESSURE SWITCH SENSESADEQUATE DIFFERENTIAL

PRESSURE CONTACTS CLOSE

THERMOSTAT CALLS FOR HEAT, CONTACTS CLOSE

CONTROL BOARD ENERGIZED,INDUCER ENERGIZED

CONTINUOUS SAFE OPERATION CHECK IF FLAME SIMULATION CONDITION PRESENT OR ROLL-OUTSWITCH OPENS, SYSTEM ENERGIZES INDUCER

FAN FOR 15 SECONDS AND CIRCULATOR BLOWERAT HEATING SPEED UNTIL SITUATION CORRECTION

AT ANY TIME THEGAS VALVE IS

NOT ENERGIZED

A. SEQUENCE OF OPERATIONS

START TRIALFOR IGNITION

START

VI. STARTING THE UNIT

AFTER IGNITOR WARM-UP,THE GAS VALVE IS

ENERGIZED TO OPEN

POWER IS APPLIED TO THE SILICON NITRIDE

IGNITOR. IGNITOR WARM-UP IS 17 SECONDS

VI. STARTING THE UNIT


33

AFTER DELAY-TO-FAN--ONPERIOD ENDS, CIRCULATING

AIR FAN IS ENERGIZED ATHEATING SPEED. THE

(OPTIONAL) ELECTRONICAIR CLEANER AND

HUMIDIFIER ARE ENERGIZED.

IF IGNITION ATTEMPT IS UNSUCCESSFUL, ONEMORE RETRY WILL BEMADE BEFORE THE

CONTROL BOARD GOESINTO SYSTEM LOCKOUT.

THE RETRY SEQUENCEPROVIDES A 60 SECONDWAIT BEFORE IGNITION

RETRY. RETRY IS ATTEMPTED WITH AN

ADDITIONAL 10 SECONDSOF IGNITOR WARM-UP TIME.

IF FLAME IS DETECTED,THEN LOST, THE CONTROLBOARD WILL REPEAT THE

INITIAL IGNITION SEQUENCEFOR A TOTAL OF SIX

RECYCLES. AFTER SIX UNSUCCESSFUL RECYCLEATTEMPTS, THE CONTROL

WILL GO INTO SYSTEM LOCKOUT.

AFTER THE DELAY-TO-FAN-OFF PERIOD ENDS,THE CIRCULATING AIRFAN AND (OPTIONAL)

ELECTRONIC AIR CLEANERARE DE-ENERGIZED.

MAINBURNER

OPERATION

END OF CYCLE

CALLFOR HEATSATISFIED

IF SYSTEM IS IN LOCKOUT, THE MODULE WILL RESET ITSELFAFTER 60 MINUTES OR MAYBE MANUALLY RESET BY

INTERRUPTING THE POWERTO THE FURNACE AT THE

DISCONNECT OR INTERRUPTINGTHE CALL FOR HEAT AT THE THERMOSTAT. IF THIS DOES NOT RESTART THE SYSTEM,

REFER TO THE TROUBLESHOOTINGSECTION OF THIS MANUAL.

WHEN THERMOSTAT IS SATISFIED, CONTACTSOPEN AND THE GAS

VALVE IS DE-ENERGIZED.AFTER PROOF OF FLAMELOSS, INDUCER STARTS5 SECOND POST SURGE

AND (OPTIONAL) HUMIDIFIERIS DE-ENERGIZED. THE

DELAY-TO-FAN-OFF PERIODBEGINS (180 SECONDS)


34

VII. TROUBLESHOOTING

THIS SECTION IS ONLY TO BE PERFORMED BY TRAINED, QUALIFIED SERVICE

PERSONNEL, AND NOT BY THE FURNACE OWNER.

NOTICE: BEFORE TROUBLESHOOTING, FAMILIARIZE YOURSELF WITH THE

START UP AND CHECKOUT PROCEDURE. ALL INSTALLATION AND

SERVICES MUST BE PERFORMED BY QUALIFIED HEATING CONTRACTORS

When testing electrical equipment, always follow standard electrical


Note – check diagnostic code through view port prior to removal of door.

1. Check for line voltage (110-120VAC) to the furnace. If there is no line voltage

applied to the furnace, check that disconnecting switch is “on”, fuses or circuit

breakers have not blown or tripped.

2. Make sure thermostat is “calling for heat”.

3. Check for adequate fuel supply and pressure. Are all the fuel shutoff valves

open?

4. To assist you in troubleshooting this furnace, it is equipped with an integrated

ignition control with diagnostics. These diagnostics evaluate what malfunction

the control system has experienced and will activate a flashing light on the

control in different sequences to help pinpoint the failure.


35

DIAGNOSTIC FEATURES

The integrated control continuously monitors its own operation and the operation

of the system. If a failure occurs, the LED will indicate a failure code as shown

below. If the failure is internal to the control, the light will stay on continuously. In

this case, the entire control should be replaced, as the control is not field-

repairable.

If the sensed failure is in the system (external to the control), the LED will flash

in the following flash-pause sequences to indicate failure status (each flash will

last approximately 0.25 seconds, and each pause will last approximately 1

second).

LED Off - No power to control, pushbutton switch pressed, or control fault

LED steady ON (Any color) - Control hardware fault detected

Slow Green flash - No call for heat, no active errors

Slow Orange flash - Call for heat present, no active errors

1 RED flash - High limit switch open

2 RED flashes - Pressure switch open with inducer on

3 RED flashes - Pressure switch closed with inducer off

4 RED flashes - 1 hour lockout code

5 RED flashes - Incorrect line voltage polarity or incorrect polarity on 24 VAC

line from transformer

6 RED flashes – Too many limit trips in one call for heat

7 RED flashes – Pressure switch cycle lockout

8 RED flashes - Too many flame dropouts detected

9 RED flashes – Not Used

10 RED flashes – Flame present with gas valve off

Rapid flash – Incorrect 24 VAC phasing/twinning error

: Power must be disconnected before servicing.


36

IS ROOMTEMPERATURE

ABOVE 90 DEGREES F?

TURN T'STATSETTING ABOVE

ROOM TEMP.

COOL THE THERMOSTAT

IS THE TRANSFORMERSUPPLYING 24 VOLTS

TO THE THERMOSTAT?

REPLACETHERMOSTAT

IS INTERNAL DAMAGEPRESENT ON THETRANSFORMER?

CHECK INPUTPOWER, DOOR

INTERLOCK,SERVICE SWITCH

AND FUSES.

No No

Yes

Yes

REPLACE TRANSFORMER

No

Yes

Yes

No No

Yes

ARE WIRES CONNECTEDPROPERLY?

No

CORRECT WIRECONNECTIONS

No

Yes

Yes

No

Yes

IS THE INDUCERBLOWER OPERATING?

Yes

TROUBLESHOOTING GUIDETHE SYSTEM IS STARTED BY SETTING THE THERMOSTAT TO CALL FOR

HEAT. THE FOLLOWING SHOULD HELP ESTABLISH THE TYPE OFMALFUNCTION OR DEVIATION FROM THE NORMAL OPERATION.

TO USE THIS DIAGRAM, YOU JUST NEED TO FOLLOW THE INSTRUCTIONS IN THE BOXES.

IS THERE 24 VOLTSACROSS "R" & "C"

AT THE INTEGRATEDCONTROL MODEL?

CHECK CONTINUITY& PROPER

CONNECTIONSREPLACE 24V

TRANSFORMER

TURN THERMOSTAT TO CALL FOR HEATDOES THERMOSTAT MAKE?

IS ROOM TEMPERATUREBELOW SETTING?


37

CHECK WIRING TO INDUCERAND IF OK, REPLACEINDUCER ASSEMBLY.

AFTER HOT SURFACEIGNITOR WARM-UP,

DOES GAS VALVE OPEN?

CHECK WIRING TOHOT SURFACE IGNITOR

AND IF OK, REPLACEHOT SURFACE IGNITOR ASSEMBLY.

Yes

Yes

No

Yes

Yes

Yes

YesYes

CHECK WIRING TO GASVALVE AND IF OK,

REPLACE GAS VALVE.

DOES THE HOT SURFACE

IGNITOR ENERGIZEAND GLOW?

IS THERE LINE VOLTAGEACROSS INDUCER POWERTERMINALS "IND" & "IND N"

AT THE INTEGRATED CONTROL?

CHECK THE INTEGRATEDCONTROL DIAGNOSTIC LED

LAMP. RESET BY INTERRUPTINGPOWER TO CONTROL FOR MORE

THAN ONE SECOND. IF LED STAYSON CONTINUOUSLY, REPLACE

INTEGRATED CONTROL.

IS THERE VOLTAGE PRESENTAT THE HOT SURFACE IGNITOR TERMINALS

"IGN" & "IGN N" AT THE INTEGRATED CONTROL?

No

NoCHECK THE INTEGRATED CONTROLDIAGNOSTIC LED LAMP. RESET BY

INTERRUPTING POWER TO CONTROLFOR MORE THAN ONE SECOND. IFLED STAYS ON CONTINUOUSLY,

REPLACE INTEGRATED CONTROL.

SAME AS ABOVE.NoNo

CHECK ACROSS "MV"TERMINALS ON INTEGRATED

CONTROL FOR 24 VOLTS DURINGTHE 5 SECOND FLAME PROVING

PERIOD AFTER IGNITOR WARM-UP.IS THERE 24VOLTS?


38

CHECK FOR PROPERMANIFOLD PRESSURE.

No

Yes

Yes

Yes

AFTER GAS VALVEOPENS, DO THE

BURNERS IGNITE?

ADJUST TO 3.5" FOR NATURAL GASOR 10.0" WC FOR LP GAS

IS IGNITORPOSITIONED CORRECTLY?

REPOSITION TOCORRECT LOCATION.

DO BURNERS STAYLIT PAST PROOF

OF FLAME CHECK?

Yes

CHECK ACROSS THECIRCULATING AIR

BLOWER TERMINALS"CIR N" & "HEAT"

FOR PROPER VOLTAGE.

REPLACE THEINTEGRATED CONTROL.

NoNo

Yes

DOES THE CIRCULATINGAIR FAN COME ON

WHEN ENERGIZED?

NoDOES BLOWERSPIN FREELY?

No

CONFIRM IFEITHER BLOWER WHEEL

IS RUBBING AGAINSTHOUSING OR MOTORSHAFT IS SPINNING

FREELY AND REPAIROR REPLACE AS NECESSARY.

Yes

Yes

IS CAPACITORWORKING PROPERLY

No

Yes

REPLACE CAPACITOR

No

REPLACE MOTOR

DOES THE INTEGRATED CONTROLENERGIZE THE

CIRCULATING AIR BLOWERAFTER THE TIME DELAY?


39

DOES SYSTEM RUN UNTILTHERMOSTAT IS SATISFIED?

CHECK ALLWIRING FOR

LOOSE CONNECTIONS.

CHECK FOR SHORT IN WIRE TOTHERMOSTAT AND CORRECT

IF NECESSARY.

DOES BURNER SHUT OFFWHEN THERMOSTAT IS

SATISFIED?

No

No No

Yes

YesYes

Yes

Yes

IS LED LIGHTON INTEGRATED

CONTROL FLASHING?

DOES THE CIRCULATINGAIR BLOWER TURN OFFAFTER THERMOSTAT IS

SATISFIED WITHIN180 SECONDS?

TROUBLESHOOTING COMPLETE. CHECK FAILURE CODES IN TROUBLESHOOTINGSECTION OF THIS MANUAL


40

VIII. DEALER MAINTENANCE

A qualified heating contractor should perform the following maintenance

procedures at the beginning of each heating season. Correct any deficiencies at

once.

c WARNING: Personal injury or property damage could result from repair or

service of this furnace by anyone other than a qualified heating contractor. Only

the homeowner/user routine maintenance described in the Users Information

Manual may be performed by the user.

c WARNING: To avoid injury from moving parts, shut off the power to the

furnace before removing blower compartment door.

c CAUTION: Label wires prior to disconnection when servicing controls. Wiring

errors can cause improper and dangerous operation.

A. ELECTRICAL:

1. Check all wiring for loose connections and any signs of damage or unusual

wear.

2. Check for correct voltage at the furnace when operating.

3. Check amp-draw on blower motor and inducer motor to assure they are not

exceeding nameplate amp rating.

4. Check for correct operation and proper settings (if manually adjustable) of all

controls.

Shut off gas and disconnect power before continuing.

B. BURNERS

If it appears that material is accumulating in the burner box, the burner box cover can

be removed and the box and burners can be vacuumed. If necessary, the burners

assembly can be removed by taking out the two screws/one on each bracket on top of

burner box and removing the burner manifold assembly (See Fig. 9). Assembly must

be pulled & tilted down in order to remove from box. If necessary, the individual tubes

can be cleaned out using compressed air to blow out the individual tubes. Care must

be taken not to damage the igniter.


41

Figure 9

C. INDUCER BLOWER ASSEMBLY

Inspect the pressure switch and tubing connections and inspect the blower/assembly

for warpage, deterioration and carbon or other build-up. If necessary, clean the

accessible portions of the housing and blower with a damp cloth. Vacuum to remove

any lint or dust from the motor assembly.

D. INSPECTING THE VENTING SYSTEM

The venting system should be inspected during the annual maintenance check-up or

during each subsequent service call.

Check all vent pipes for restrictions due to soot, or carbon build-up, as well as foreign

matter, or any materials, that cause the venting system to restrict the proper venting of


42

combustion products. If a restriction is found, the flue vent must be cleaned or

replaced to ensure proper venting.

Vent pipes should also be inspected for any signs of corrosion, deterioration, or

leakage that may cause combustion by-products to infiltrate the home or indoor

environment.

If signs of corrosion, deterioration, or leakage are evident, the vent pipe must be

replaced with a properly sized, agency-approved, vent pipe.

E. GASKETS/SEALING MATERIALS

Inspect all visible gaskets for signs of degradation, especially any seals which were

removed as part of the inspection. Replace any suspect gaskets.

F. HEAT EXCHANGER

Inspect for corrosion, pitting, warpage, deterioration, carbon build-up, and loose

gaskets in the flue pipe, burner box, and accessible areas of the heat exchanger.

G. HOUSE AIR BLOWER

Check and clean the blower wheel, housing, and compartment with a vacuum. Check

the motor nameplate and follow the motor manufacturers instructions for lubrication, if

required.

IMPORTANT: Some motors are permanently lubricated and should not be oiled.

See motor nameplate for specific instructions.

H. EXTENDED SHUTDOWN

If this furnace is shut down or off for an extended period of time, several steps can be

taken to help insure a smooth and reliable start.

ON SHUT DOWN:

1. Close the gas supply shutoff valve(s).

2. Turn the furnace power switch “off” and disconnect electrical power to the unit.

ON START-UP:

1. Have the heating system (and furnace) inspected and started by a qualified

service person.

2. Set the room thermostat above room temperature.


43

3. Open all shutoff valves in the gas supply line.

4. Turn “on” the main power at the disconnecting switch and at the furnace power

switch to start the inducer.

5. Follow the “BURNER OPERATION AND ADJUSTMENT” procedure in Section J.

IX. USER INFORMATION SECTION

A. WARNINGS AND CAUTIONS:

: If you suspect there is a problem with the furnace, pertaining to the

venting system or any other related problem, immediately contact a qualified

service agency. If a service agency is not available, contact your fuel

supplier.

: Personal injury or property damage could result from major repair

or service of this furnace by anyone other than a qualified contractor. The

user should only perform the routine maintenance described in the user

section of this manual.

: The area around the furnace should be kept free and clear of


: Do not block or obstruct air openings on the furnace casing. Do not

block or obstruct air openings communicating within the area in which the

furnace is installed.

: Do not allow the outside air intake to be blocked or obstructed by

vegetation, ice, snow, or any other materials.

: Do not use this furnace if any part has been underwater.

Immediately call a qualified service agency to inspect the furnace and to

replace any part of the electrical or control system, which has been

underwater.

: Should overheating occur or the fuel supply fail to shut off, shut off

the manual fuel supply valve to the furnace before shutting off the electrical

supply.


44

B. COMPONENT LOCATIONS

The following diagram shows a typical furnace installation and typical position of

the components referenced in these instructions.

Figure 10

C. INSPECTION AREAS

IMPORTANT: For safe operation it is the responsibility of the owner and/or user

that the burner, chimney/vent pipe, heat exchanger and controls should be

inspected every year by a qualified heating contractor.


45

1. VESTIBULE: The furnace vestibule areas or burner compartment should be

inspected by removing front door of the furnace and looking for signs of

excessive heat such as discoloration of components, materials damaged

from rust or corrosion, soot or carbon build-up.

2. EXTERIOR OF FURNACES: The furnace exterior should be inspected for

signs of excessive heat such as discoloration of materials or damage from

rust or corrosion.

3. VENT CONNECTOR: The furnace vent pipe should be inspected for signs of

rust, corrosion pitting, or holes in the pipe. Check for leakage around seams

in pipe indicated by soot or condensate streaks.

4. ROOF JACKS: The furnace roof jack should be inspected for signs of rust or

corrosion, pitting or holes, signs of excessive condensation or moisture

leaking from roof jack.

D. FILTER LOCATION AND CLEANING

c CAUTION: To avoid injury from moving part, hot surfaces or electrical

shock, shut off the power to the furnace and allow the furnace to cool

before removing furnace access door to service filter.

The air filter should be inspected each month and cleaned when dirty. Clean the

filter by soaking it in water with a mild detergent and rinsing it with clean water.

Allow the filter to air dry before reinstalling it in the furnace. Cleaning the air

filter frequently may prevent airborne contaminants from going through the

furnace and depositing in the furnace, duct system, and interior of the building.

See Figure 10, in this section, for the location of the return air filter.


46

APPENDIX A – REPLACEMENT PARTS


47


48

APPENDIX B – WIRING DIAGRAM

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